FrameTimeline marks a frame as late, yet the main thread, RenderThread, and SurfaceFlinger all seem to stay within their budgets. It is tempting to write “possibly a GPU bottleneck.” That is a risky claim: GPU frequency, GPU counters, battery current, and power rails are not tools for attributing an individual App frame to a root cause.

Parts 07 and 08 covered the rendering path from the App to SurfaceFlinger; Parts 06 and 09 covered refresh rates and CPU scheduling/frequency. This article adds an often-skipped step without repeating those topics: when a problem appears to have reached the hardware resource layer, how should GPU, devfreq, battery counters, and power rails enter the analysis of the same trace interval?

These counters are difficult because not every device provides them, and different GPU vendors use different counter names. A conclusion cannot simply say “a high GPU value means a GPU bottleneck.” FrameTimeline, RenderThread, SurfaceFlinger, the GPU timeline, frequency, and power data must be examined over the same interval.